Scripts based on `ffmpeg` to ease the make of course videos by iPad screen recording.

README.md

Scripts based on ffmpeg to ease the make of course videos by iPad screen recording.

Usage

1. Screen recording on iPad results multiple mp4 files. These files have extension .MP4. Note the extension is capitalized.
2. If needed, edit the video by iPad Photo App. Note that the edited file's extension is .mov.
3. Airdrop these files to MacBook Pro.
4. Rename all files to either ###.mp4 or ###.mov, where ### is $n$ digits where $n$ is determined by the number of files. ### should start with 001 and the numbering shall follow the order of the videos.
5. Convert all mov files to mp4 files using script mov2mp4.
6. Combine all mp4 files using script combinemp4.

Scripts

ffmpeg

The static binary of ffmpeg

mov2mp4

$ mov2mp4 1

Convert all mov files in the current folder to mp4 files. Run the command without any argument is a dry run.

combinemp4

$ combinemp4 1

Combine all mp4 files in the current folder to a single mp4 file. Run the command without any argument is a dry run.

combinemp4.sh

#!/bin/bash

DRY=$1

if [ -z "$DRY" ]; then
    DRY=true
else
    DRY=false
fi

echo "Changing *.MP4 to *.mp4"
for mp4 in *.MP4; do
    filename=$(basename "$mp4" .MP4)
    if [ "$filename" = "*" ]; then
        break
    fi
    if [ $DRY = false ]; then
        mv "$mp4" "$filename".mp4
    else
        echo  "mv $mp4 $filename.mp4"
    fi
done

echo "Combining mp4 files"
command="ffmpeg"
filter=""
n=0
for mp4 in *.mp4; do
    command="$command -i $mp4"
    filter="$filter""[$n:v:0][$n:a:0]"
    n=$((n+1))
done
filter="$filter""concat=n=$n:v=1:a=1[outv][outa]"

command="$command -filter_complex \"$filter\" -map \"[outv]\" -map \"[outa]\" out.mp4"

if [ $DRY = false ]; then
    $($command)
else
    echo  "$command"
fi

if [ $DRY = true ]; then
    echo "Please run command: combinemp4 1 to actually do the work."
fi

mov2mp4.sh

#!/bin/bash

DRY=$1

if [ -z "$DRY" ]; then
    DRY=true
else
    DRY=false
fi

for mov in *.mov; do
    filename=$(basename "$mov" .mov)
    if [ $DRY = false ]; then
        ffmpeg -i "$mov" "$filename".mp4
    else
        echo  "ffmpeg -i $mov $filename.mp4"
    fi
done

for mov in *.MOV; do
    filename=$(basename "$mov" .MOV)
    if [ $DRY = false ]; then
        ffmpeg -i "$mov" "$filename".mp4
    else
        echo  "ffmpeg -i $mov $filename.mp4"
    fi
done

if [ $DRY = true ]; then
    echo "Please run command: mov2mp4 1 to actually do the work."
fi